What Is Joint Control?
Joint control is a concept introduced by Lowenkron (1998, 2006) to explain how complex verbal behavior occurs when two or more sources of stimulus control converge on a single response. The term describes situations where a behavior is simultaneously controlled by two or more verbal operants, and the response occurs only when both sources of control are present at the same time. Joint control provides a behavior-analytic account of how individuals follow instructions, match samples to comparisons, and engage in other complex verbal tasks.
The concept is grounded in Skinner's (1957) analysis of verbal behavior but extends it by providing a mechanism for explaining listener behavior and conditional discriminations. For BCBA exam candidates, understanding joint control helps make sense of how verbal operants interact to produce complex behavior.
The Mechanism of Joint Control
Two Sources of Control
In a joint control account, the critical event is the simultaneous presence of two types of verbal control over the same response. Consider a simple example: a teacher says "point to the red one" (an auditory stimulus), and the child scans an array and points to the red item. What controls the pointing response?
According to the joint control account, the child engages in covert echoic behavior (repeating "red" to themselves) while scanning the array. When the child sees the red item, a tact response ("red") is evoked by the visual stimulus. At the moment when the echoic response ("red") and the tact response ("red") converge on the same word, joint control occurs, and the child points to the matching item. The pointing response is controlled jointly by the echoic (maintaining the instruction) and the tact (identifying the visual stimulus).
The Role of Self-Echoic Behavior
A key component of the joint control account is self-echoic behavior, where the individual covertly or overtly repeats the instruction or relevant verbal stimulus while scanning for the match. This echoing serves as a mediating response that bridges the temporal gap between hearing the instruction and encountering the correct stimulus. Without the self-echoic, the auditory stimulus from the instruction would fade before the individual encounters the matching item, and joint control could not occur.
This explains a common clinical observation: young learners and individuals with limited verbal repertoires often repeat instructions aloud while searching for the correct response. They may say "red, red, red" while scanning an array. This overt self-echoic behavior eventually becomes covert (internal) as the repertoire develops, but its function remains the same: maintaining one source of verbal control until it can converge with another.
Clinical Applications
Teaching Listener Responding
The joint control account has direct implications for teaching listener behavior. If a learner is struggling with receptive identification (e.g., "touch the ___"), the clinician should assess whether the learner has the component skills needed for joint control:
- Echoic repertoire: Can the learner echo the target word?
- Tact repertoire: Can the learner tact (label) the items in the array?
- Scanning: Does the learner systematically scan the array?
If any of these component skills is missing, joint control cannot occur, and the listener response will not emerge. The clinician should build the missing skills rather than simply repeating receptive identification trials. This analysis explains why some learners can tact items but cannot select them receptively, or vice versa, and it guides the clinician toward targeted skill-building.
Teaching Sequelic Responding
Joint control is particularly relevant for understanding sequelic responses, which are verbal behaviors that follow and are controlled by another verbal stimulus. When a speaker says "The capital of France is ___" and the listener fills in "Paris," the response is jointly controlled by the intraverbal fill-in prompt and the learner's previously conditioned intraverbal relationship between "capital of France" and "Paris."
Problem Solving and Reasoning
Lowenkron's joint control analysis extends to more complex behaviors like problem solving. When an individual is given a multi-step instruction (e.g., "find the tool that is both red and small"), joint control requires maintaining two criteria (red and small) simultaneously and responding only when an item meets both. The individual engages in self-echoic behavior for both features and selects the item where both tact responses converge. This analysis has implications for teaching conditional discriminations and multi-criteria sorting tasks.
Relationship to Other Verbal Operants
Joint Control and the Tact
The tact is one of the two most common operants involved in joint control. In typical match-to-sample tasks, the tact provides the visual-stimulus-based control that converges with the auditory-stimulus-based control from the instruction. Strong tact repertoires are therefore prerequisites for many joint control situations.
Joint Control and Intraverbals
Intraverbal behavior also involves joint control in many cases. When responding to a question like "What do you drink from?", the individual may engage in covert echoic behavior ("drink from, drink from") while cycling through previously conditioned intraverbal responses until the convergence point ("cup") is reached. This analysis explains why intraverbal training often benefits from first establishing strong tact and echoic repertoires.
BCBA Exam Preparation
Joint control is a conceptually complex topic that appears on the BCBA exam. Key points to study:
- Joint control involves two or more simultaneous sources of verbal control over a single response
- Self-echoic behavior serves as a mediating response that maintains one source of control
- The echoic and the tact are the two most commonly involved operants
- Joint control provides a behavior-analytic account of listener behavior, matching, and conditional discriminations
- Lowenkron is the key researcher associated with the formal analysis of joint control
- Clinical assessment should evaluate component skills (echoic, tact, scanning) when joint control is not occurring
When you encounter exam questions about how a learner selects the correct item from an array after hearing an instruction, consider whether the answer involves a joint control analysis. This is one of the more advanced verbal behavior topics, but understanding it will help you with multiple question types on the exam.